1. Field of the Invention
The present invention relates to a cloth presser in a sewing machine stitching in zigzag and provided with a thread end holder capable of cutting the thread end used at the starting of sewing and remained on the surface of the sewn cloth.
2. Description of the Prior Art
In a prior art cloth presser in a sewing machine stitiching in zigzag and provided with an automatic thread cutter having a movable knife inserted into a recess of a cloth presser bottom plate, a needle thread can be cut by the movable knife or manually at the completion of the sewing operation. If the new sewing operation is started at the state where an end of the thread is not held but left as it is, at a first stitch the needle penetrates the sewn cloth while the needle thread is hooked by a tip of a full rotatable hook under the sewn cloth. The thread end of the needle thread is drawn under the sewn cloth and tangled with the seams while it effects a couple of stitches to produce an inferior quality of the seam, the so-called waste or bird nest.
In the case where the end of the needle thread is pressed by the cloth presser at the start of sewing operation of the cloth, the thread end is not inserted under the sewn cloth. However, the thread end is retained longer on the upper surface of the sewn cloth which requires a step for cutting this retained thread to improve the quality.
In the case where no first stitch is formed on a cloth to be sewn, the so-called empty sewing, the thread end is not subject to increased friction caused by the cloth so that the needle thread slips off from the needle hole and the cloth can not be sewn.
To solve the problem of inconvenience at the start of sewing operation, there is disclosed a means for holding the thread end of the needle thread in Japanese Utility Model Laid-Open Publication No. 58-5592 which is illustrated in FIG. 9. In FIG. 9, both a hook a provided at the tip end of an elastic metal lever b which is reciprocally and swingably driven by a rotary solenoid S and a presser lever 13 are moved toward the tip of needle threads B hung down from needles A and moved backward while holding the end of the needle threads B.
Japanese Utility Publication No. 58-5592 solves the problem of inconvenience created by the free end of the needle thread. However, is needed a finishing step for cutting the remained thread since greater force affects the thread extended between the thread end holder and the seam made by the first stitch, and the thread slips off from the thread end holder and retained on the sewn cloth.
Japanese Utility Model Laid-Open Publication No. 62-109079 discloses a cloth presser in a sewing machine provided with a thread end holder for preventing the thread end at the start of the sewing operation from being retained on the surface of the sewn cloth for a long time. However, this invention is difficult to use directly on a cloth presser in a sewing machine stitching in zigzag and provided with a thread end holder in which the needle position is varied, since it thread is difficult to cut the needle thread with safety.